Flesh-eating pitcher plants living in a bog in Canada have for the first time been spotted regularly feasting on salamanders.
The carnivorous plant – also known as a “turtle sock plant” – was previously believed to feed almost exclusively on spiders and small insects who fell into their bell-shaped leaves and drowned in small pools of water. When researchers found creatures like rats and frogs in pitcher plants they assumed it was an accidental one-off.
However, biologists from the University of Guelph found these plants regularly devour young spotted salamanders, which they can digest in less than two weeks.
It’s still not known how the salamanders end up in the pools, but it could be because they were trying to catch insects attracted to the plant. Others may have entered in a bid to escape predators.
Prey caught inside the plant’s specialised leaves are broken down by digestive enzymes.
Heat, starvation or infection by pathogens, may also kill salamanders trapped, according to lead researcher Dr Alex Smith.
These amphibians – each around the length of a human finger – are highly nutritious for the plants that like growing in nutrient-poor acidic bogs.
Some trapped salamanders died within three days, while others lived for up to 19 days.
“I hope and imagine that one day the bog’s interpretive pamphlet for the general public will say, ‘Stay on the boardwalk and watch your children. Here be plants that eat vertebrates,’” said Dr Smith.
Other flesh-eating plants grow in nutrient-poor environments around the world. They include sundews, which use their sticky leaves to catch insects, and the Venus flytraps which shut their “traps” when an insects lands on it.
Meat-eating pitcher plants have been known about since the eighteenth century and there are nearly 600 varieties around the world.
One species discovered a decade ago in Asia consumes mostly insects and spiders but also captures small birds and mice.